It is estimated that children aged 0 - 14 years account for a third of all tuberculosis (TB) cases. It is reported that childhood TB contributes 15 - 40% o TB cases in developing countries but since unlike adult TB, childhood TB has not received a lot of attention, this estimate could be greater. TB is also the leading cause of death in HIV infected individuals. In 2010, there were 8.8 million newly diagnosed TB cases globally, of which 12 - 14% was HIV positive. Of the HIV positive TB cases, approximately 81% were from Africa. In Uganda, there were 70,000 newly diagnosed TB cases. Children get infected with TB from living in close contact with adults who have TB. However, the true burden of TB among children is not known. Further, the outcomes of TB treatment among children treated for active TB disease are not known. For instance the international treatment success rate (TSR) ranges from 70 - 85% whereas the Uganda treatment success rate (TSR) is 68%. However, the TSR for childhood TB is not known. It should be of concern whether children complete treatment, get cured or fail on treatment since children depend on adults for their care and they act as future reservoirs of TB disease. However, not much attention has been paid to them since they were believed not to contribute to the TB burden. The objective of this study therefore, is to determine the burden of latent and active TB and their treatment outcomes among HIV infected children in Uganda. This will be achieved through the following specific aims: 1) To determine the incidence of latent and active TB among children attending a pediatric HIV care facility in Kampala, Uganda; 2) To determine the treatment outcomes of children diagnosed with active TB and 3) To examine the clinical factors associated with development of active TB. We shall conduct a prospective cohort study in which we shall recruit and follow up HIV infected children. The children will be screened for latent and active TB using a revised intensified case finding form (RICF form), Tuberculin Skin Test (TST) and the T-SPOT(R).TB assay. Active TB will be diagnosed though x-rays, sputum microscopy and culture. They will be followed up for three years and monitored for TB development. Those diagnosed with TB will be followed up to study the treatment outcomes. It is expected that this study will yield information on the TB burden and treatment outcomes that will inform the National TB program on the burden of latent and active TB in HIV infected children. This may give an estimate of the burden of latent and active TB among HIV negative children. Use of the RICF alongside the TST and T- SPOT(R).TB will help in deciding whether the RICF can effectively identify TB suspects. Treatment of children with latent TB and general treatment of HIV-infected children with isoniazid will also provide essential information as the country prepares to adopt the new WHO Isoniazid Preventive Therapy (IPT) guidelines.